High-end motor systems such as those used in hybrid vehicles are often controlled using one or more high power modules. A traction drive system, for example, consists of a drive unit (motor and gearbox) and an inverter for controlling the motor. The inverter and drive unit are typically located in a separate chassis.
The inverter generally includes an IGBT (Insulated Gate Bipolar Transistor) and a large silicon diode. These power components are mounted (e.g., soldered) on DBC (Direct Bond Copper) substrates, which comprise copper layers with an insulating ceramic layer sandwiched in between. Wire bonds or other interconnects are used to provide electrical connectivity between a busbar (typically a thick bar of copper) and the various die, where the busbar provides electrical communication with external systems.
It is desirable to reduce the complexity, mass, and volume of such electronic components while improving their heat transfer characteristics. Typically, known busbar assemblies typically utilize large heat sinks or air-cooled units, thus resulting in additional components, increased cost, and additional required space.
Accordingly, there is a need for improved heat transfer methods in power devices such as those used in connection with motor control inverters. Other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.